• Korean Journal of Psychosomatic Medicine
• /
• v.9 no.1
• /
• pp.81-92
• /
• 2001

Stress has been linked to the pathophysiology and pathogenesis of various psychiatric illnesses. Over the past few years, our understanding of the brain and neuroendocrine systems that are linked to stress responses has increased enormously. This article reviews a series of animal and human studies to understand what are the central pathways by which stress is perceived, processed, and transduced into a neuroendocrine response. We focus on the limbic-hypothalamic-pituitary-adrenal(LHPA) axis and several neurotransmitter systems such as norepinephrine, CRF, serotonin, acetylcholine, and dopamine. LHPA stress circuit is a complex system with multiple control mechanisms which are altered in pathological states. CRF and related peptides in the central nervous system appear to enhance behavioral responses to stressors. Norepinephrine systems are also activated by stressors and cause the release of catecholamines from the autonomic nervous system. CRF-norepinephrine interaction makes a feed-forward system which may be important for an organism to mobilize not only the pituitary system but also the central nervous system, in response to environmental challenges. The interactions among several neurotransmitters and endocrine systems appear to play key roles in mediating various behavioral and psychological stress responses involving abnormal responses to stressors such as anxiety and affective disorders.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1993.04a
• /
• pp.158-158
• /
• 1993

노화현상에 따른 여러 가지 병태생리조건의 형성과 난치성 성인병질환의 발병 및 진행과정에 활성산소류들과 이들에 의해 유도되어지는 free radical이 관여하고 있다는 증거가 여러연구진에 의해서 보고되어지고 있다. 산소를 이용하여 생명현상을 이어가는 생물체들은 필연적으로 활성산소들을 생성하는 생화학적 산화반응기구를 효율적으로 활용하면서 항상성을 유지시키고 있다. 그러므로 활성산소의 생성과 분해과정의 평형유지는 생물학적으로 대단히 중요한 의미를 갖고 있다. 임상적으로 alcohol은 질병의 악화 내지는 질환의 발병조건을 조성하는 병태생리기구에 기여할 것으로 생각되어 대부분의 환자에게 금주시키고 있으나 그 작용기전에 대해서는 충분히 설명되지 못하고 있다. 본 연구에서는 alcohol을 급ㆍ만성으로 실험동물에 투여하고 생체에서 활성산소 생성에 중요한 역할을 하는 xanthine oxidase와 aldehyde oxidase의 활성변화를 관찰하면서 전자의 형전환속도와 과산화지질 생성속도와의 상관성을 중점 비교 관찰하므로서 alcohol성 간손상 실험 model을 계획하였다. 간 및 신장조직에서 alcohol에 유래되는 활성산소의 생성계에 관여하는 효소 활성의 변화와 조직의 과산화지질 생성반응 속도는 alcohol의 투여방법, 기간, 시간(diurnal variation), 나이 및 암수에 따라 다르게 나타남을 관찰할 수 있었다.

• The Journal of the Korean dental association
• /
• v.25 no.8 s.219
• /
• pp.735-739
• /
• 1987

implant라는 것은 생리학적으로 생체에 있어서 이물이라는것을 인식해야 한다. 또 그 일부를 상부구조물을 제작하기 위하여 구강내에 노출시킴으로써 연조직과의 접촉부위가 감염으로 염증상태를 지속하고 있다. 그뿐아니라 저작시에 교합압에 의한 위격으로 골내에 여러 가지 변화를 일으킨다. 이와같이 생체내에 이물를 implant 하였을 때 생기는 반응은 생체의 방어기전으로서 염증을 일으키는데 이 염증의 진도에 따라 동화, 흡수, 배제중의 어느 하나로 결말짓게 된다. 따라서 implant를 시술하였을때 생기는 조직의 반응을 최소한으로 감소하기 위한 생물학적 적응조건으로서 재료, 약물, 기구, 시술방법 등을 잘 선택하는 것이 implant의 임상응용에 요절이 되는것이다. implant의 종류는 실로 다양다종이다. 그러나 어떤 implant와 시술방법을 선택하든지 악골에 접착, 또는 식위하여 견고하게 장착되어 그 implant된 자체를 통하여 가장 천연치에 가까운 기능을 얻는것이 implant의 시술목적이다. 임상의가 implant를 시술하면서 이것이 과연 성공할것인가? 즉 저작효율과 내구연한이 얼마나 갈것인가 우려하지 않을수 없다. 그러므로 그 우려를 덜고 성공으로 이끄는 임상상의 문제점을 찾아 논하기로 한다.

• Journal of fish pathology
• /
• v.5 no.2
• /
• pp.159-164
• /
• 1992

The skin of fishes is also the important external barrier against a variety of the environmental detrimental agents, allowing normal internal physiological function, so its condition is very important in many disease processes. Since fishes are aquatic, morphologically and physiologically they posses specific characteristics lacking in terrestial animals. Thus, it is necessary to keep in mind various specific histologic characteristics for a precise interpretation of the histopathological lesions. In the normal environment the fish skin is more subtly adapted for its physiological requirements as a limiting barrier than the skin of higher terrestial vertebrates. However, its delicacy makes it high vulnerable to damage in fish culture facilities or polluted waters. Although changes in the skin of fish such as discoloration, ulcerative lesions, are the the most readily observed clinical features of fish, there is a wide variety of possible responses, which are best considered in terms of their site within the skin. Up to now, there are relatively few sytematically described information on the histological structure of the teleost skin as well as integrated reviews of the range of pathological processes that can occur in teleost skin. Therefore it was tried in this article to rearrange the information already described by other investigators on the histological structure and histopathological changes of teleost skin.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.26 no.1
• /
• pp.74-82
• /
• 2002

The present study is aimed to investigate the effect of the safety hat on the balance of body temperature by observation of the physiological response under hot working environment. The experiment was carried out in a climate chamber of 3$0^{\circ}C$, 50%RH for 70 minutes. To compare the two kinds of safety hat, 5 healthy male subjects worn safety hat without hole (called 'without hole') or safety hat with hole (called 'with hole') according to a randomized cross-over design. The main results of this study are as fellows: Rectal temperature and heart rate were significantly lower level in 'with hole'than in 'without hole'. The mean skin temperature was significantly higher in 'without hole'than in 'with hole'. Blood pressure were significantly low in 'with hole'. Sweat rate which was measured by weight loss before and after experiment was higher in 'without hole'. In subjective ratings, subjects replied more hot, more uncomfortable and more wet, they felt more fatigue in condition of 'without hole'. Work ability which was measured by a grip strength dynamometer was higher in 'with hole'. Safety hat which can be used for safety of the brain in work place is meaningful device of behavioral thermoregulatory response under the hot working environment. The safety hat which is designed for proper ventilation and hygiene can maintain the homeostasis of body temperature by releasing body temperature efficiently.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.18 no.2
• /
• pp.78-82
• /
• 2014

Purpose The physiological and biochemical responses of healthy men and women to life stress were measured in order to investigate the correlation between these two responses under the normal situation. Materials and Methods The population of the research is some randomly chosen health college students located in Daejeon City during the period from August to September 2014, and the sample of 94 students. Heart rate variability (HRV), blood pressure (BP) were selected as physiological stress indices and serum cortisol level was used as a biochemical stress biomaker. The data which is collected used SPSS19.0 programs and frequency and percentage and T-test, correlation. Results Male showed the significant higher value of serum cortisol level (p<0.05), BP (p<0.05), and LF/HF ratio of HRV (p<0.05) than female. The difference of BP between correlated significantly with serum cortisol level (p<0.05). The LF/HF ratio of HRV also correlated significantly with serum cortisol level (p<0.05) Conclusion We suggest that LF/HF ratio of HRV and BP may be good indices for the assessment of life stress.

• The Journal of the Acoustical Society of Korea
• /
• v.35 no.1
• /
• pp.63-73
• /
• 2016

It is widely acknowledged that the human auditory system is organized tonotopically and people generally listen to sounds as a function of frequency distribution through the auditory system. However, it is still unclear how acoustic features of speech sounds are indicated to the human brain in terms of speech perception. Thus, the purpose of this study is to investigate whether two sounds with similar high-frequency characteristics in the acoustic analysis show similar results at the level of auditory brainstem. Thirty three young adults with normal hearing participated in the study. As stimuli, two Korean monosyllables (i.e., /ja/ and /cha/) and four frequencies of toneburst (i.e., 500, 1000, 2000, and 4000 Hz) were used to elicit the auditory brainstem response (ABR). Measures of monosyllable and toneburst were highly replicable and the wave V of waveform was detectable in all subjects. In the results of Pearson correlation analysis, the /ja/ syllable had a high correlation with 4000 Hz of toneburst which means that its acoustic characteristics (i.e., 3671~5384 Hz) showed the same results in the brainstem. However, the /cha/ syllable had a high correlation with 1000 and 2000 Hz of toneburst although it has acoustical distribution of 3362~5412 Hz. We concluded that there was disagreement between acoustic features and physiology outcomes at the auditory brainstem level. This finding suggests that an acoustical-perceptual mapping study is needed to scrutinize human speech perception.

• Journal of Marine Life Science
• /
• v.7 no.2
• /
• pp.171-179
• /
• 2022

The present study investigated the survival rate, respiration rate, plasma stress index, and histological changes according to exposure time of cultured red seabream (Pagrus major) and olive flounder (Paralichthys olivaceus) exposed to Cochlodinium polykrikoides red tide. Fish cultured in natural seawater were used as the control group. Cochlodinium polykrikoides density was set to 5,500±200 cells·ml^-1 in the experimental groups. All red seabreams died within 1 hour of exposure to red tide, whereas all olive flounders died within 5 hours of exposure. Analysis of physiological response revealed that in red seabream, plasma glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), catalase (CAT), and glutathione peroxidase (GPx) concentrations were increased; plasma glucose and superoxide dismutase (SOD) concentration were decreased. Meanwhile, in olive flounders, plasma cortisol, GOT, and GPT concentrations were increased; plasma glucose concentrations were increased during the first hour of exposure, followed by decrease after 5 hours; and plasma SOD, CAT, and GPx concentrations decreased during the first hour of exposure. Histological analysis revealed structural damage to the gills of both red seabream and olive flounder. In conclusion, the exposure of red seabream and olive flounder to Cochlodinium polykrikoides red tide at the density of 5,500 cells·ml^-1 induces oxidative stress, which activates antioxidant defense mechanisms, ultimately leading to liver and gill damage.

• Journal of Life Science
• /
• v.1 no.1
• /
• pp.24-29
• /
• 1991

생물화학에서 취급되고 있는 대부분의 효소는 metabolic map에 나타난 대사의 각각의 단계를 촉매하는 효소로써 생물학적 혹은 생리학적인 의의가 해명되어 있다. 그러나 현재로서는 metabolic map과는 관계없는 효소로 취급되는 것도, 생물이 생명유지를 위해서는 필수적인 어떤 화학반응을 촉매하고 있는 것으로 생각되고 있다. 생체내에 존재하는 무수한 효소 중에서 개개의 특이적인 효소의 성질을 해명하기 위해서는 촉매성의 기반이 되고 있는 효소단백질의 구조라든가 성질을 검토하지 않으면 안 된다. 그렇게 하기 위해서는 될 수 있는 한 목적효소를 생체내에 존재할 때와 같은 상태로 순수하게 정제할 필요가 있다. 일반적으로 효소류는 생체내에 존재할 때는 상당히 안정하게 유지되지만, 일단 세포 외에 추출되면 생체 내에서의 생리적 조건으로부터 벗어나기 때문에 서서히 실활되는 경우가 많다. 따라서 효소의 취급에는 안정성을 고려한 세심한 주의가 필요하다.

• Journal of Life Science
• /
• v.20 no.11
• /
• pp.1718-1724
• /
• 2010

Bioactive and chemical properties of silkworm powder (SP) degradation by fruit extract containing the proteolytic enzymes of kiwifruit, papaya, pineapple and pear were investigated. Silkworm powder was incubated with extracts from each fruit at $60^{\circ}C$ for 24 hr. Protein content was slightly higher in the SP treated with fruit extract than that in the control SP. Major minerals were K, Ca, Mg, and Zn. Major fatty acids were linolenic acid, oleic acid, and palmitic acid. When total protein patterns were analyzed by SDS-polyacrylamide gel electrophoresis (PAGE), silkworm protein was strongly degraded by the treatment of fruit extract from pineapple, papaya, and pear, but little silkworm degradation was observed in kiwifruit extract treatment. Fibriolytic activity was only detected in the SP by the fruit extract treatments from papaya and pear. DPPH radical scavenging activity was slightly stronger in the SP treated with fruit extract than that in silkworm powder. However, all these samples exhibiteda relatively low activity compared with the butylated hydroxytoluene (BHT). These results may provide the basic data for understanding the biological activities and chemical characteristics of SP treated with fruit extract for development of functional foods.